1. Field of the Invention
The present invention relates to the field of scissors, shears and similar cutting implements and more particularly to a novel such cutting implement having removable or replaceable shank inserts or cutting blades therefor.
2. Brief Description of the Prior Art
In the past, major inconveniences to which a surgeon, barber or other worker who constantly used scissors had to contend with was the problem of maintaining a sharp, keen cutting edge on the instrument in order to perform the best work. The user would have to continually maintain these sharp instruments in order to obtain proper performance. This problem is also presented to a surgeon who, in addition, is faced with the problem of sanitation of his surgical scissors. Therefore, attempts have been made to utilize interchangeable cutting blades adapted to be mounted on the shanks of scissors or the like for easy and quick removal without damage to the latter. However, problems have been encountered which stem largely from the fact that insertion of removable blades into the respective shanks is not guided and relies solely on feel and visual observation. Also, removal of blades, when dull or damaged, is difficult and generally requires the two hands of the user to successfully eject or remove blades. In other instances, problems have been encountered with premature release or lack or retention for the blades on the shank so that blades sometimes dislodged and fell from the shank when in use.
When such prior implements are used in specialized situations, such as when surgical instruments are employed, extremely hard and dense materials are used for producing the scissors or implement. Such compositions are difficult, and therefore expensive to drill, form or otherwise provide the necessary recesses, openings, apertures or the like in order to fabricate a high performance instrument. The cost involves not only highly skilled labor but the cost of cutting implements which are required to form the surgical steel used in the fabrication of such instruments.
Therefore, a long standing need has existed to provide a cutting implement which not only has replaceable blades, but which is self-indexing or registering so that the replaceable blade may be automatically installed or ejected from its location on the implement. Additionally, it is preferred to have a positive retention means for holding the replaceable blade in position so that it will not be inadvertently dislodged.